Feline viral respiratory diseases are highly contagious, often serious
illnesses of cats that can spread rapidly
through a multicat home, a cattery, or a shelter. They are one of the most
common infectious disease problems a cat owner is likely to encounter. Although
few adult cats die of upper respiratory disease, the death
rate among young kittens approaches 50 percent.
Although these diseases are highly contagious among cats, they cannot be
transmitted to humans. Cats also cannot catch our colds. This is because the
viruses that attack cats do not affect humans, and vice versa.
Recently, it has been recognized that two major viral groups are responsible
for the majority of clinical upper respiratory infections in cats (80 to 90
percent). The first is the herpesvirus group, which includes feline viral
rhinotracheitis (FVR). The second is the calicivirus group, which includes
feline caliciviral disease.
Other viral agents, especially those of the reovirus group, cause feline
viral respiratory illness. They account for a minority of cases.
There are two distinct stages in the feline viral respiratory disease
complex. The acute stage is followed by the chronic carrier state.
Acute Viral Respiratory Infection
There is considerable variation in the severity of illness. Some cats have
mild symptoms, while in others the disease is rapidly progressive and sometimes
The disease is transmitted from cat to cat by direct contact with infected
discharge from the eyes, nose, mouth; by contaminated litter boxes, water
bowls, and human hands; and rarely, by airborne droplets. The virus is stable
outside the host for as short as 24 hours or as long as 10 days, depending on
Clinical signs appear 2 to 17 days after exposure and reach maximum severity
10 days later. Illness begins with severe bouts of sneezing lasting one to two days. This is followed by
conjunctivitis and watery
discharge from the eyes and nose, which may suggest a cold or flu. By the third
to fifth day, a cat exhibits fever, apathy, and loss of appetite. The eye
and/or nasal discharge becomes mucoid
or purulent. Cats with obstructed nasal passages breathe with their mouths